Professor of Biochemical Engineering.
I am interested in using chemical engineering tools of modelling and the control of reaction and mass transfer to develop the ability to make new products for the biotechnology and food industries. We are exploring with colleagues a number of different avenues which exploit the ability of membranes and chromatographic columns to fractionate macromolecules with functional properties for foods, with properties that make them desirable for use in cell culture.
Operating membrane filtration below a critical flux results in fouling of the membrane. It depends on hydrodynamics, particle size charge on the membrane. We are interested in developing models to predict fouling and critical flux and verify existing theories across a wide range of experimental conditions. Operating in the near critical flux region has meant improved fractionation in both ultrafiltration and microfiltration applications. The Bath group is one of the larger groups in Europe working in the membrane field and involves many colleagues. We are collaborating with several industries in order to develop new products using these techniques.
Selected publications
Dengxi Wu, J.A. Howell and R.W. Field, Critical flux measurement for model colloids, J.Membrane Science 152 (1999) 89.
J.A. Howell, D.Wu and R.W. Field , Transmission of bovine albumin under controlled flux Ultrafiltration, J.Membrane Science 152 (1999) 117
- We are working to create new materials for use in skin replacement applications such as chronic skin ulcers. The techniques include the development of bioreactors in which to cultivate autologous cells (from the patient) in an environment similar to that of the prospective application. Multiple cell types are grown on a matrix scaffold. Problems include ensuring cell adhesion in a flow field and ensuring rapid proliferation before implantation. The work is collaborative with Medical Sciences and Dr Julian Chaudhuri. We are currently supported by CASE awards and a DTI SMART award through TSL Ltd.
Selected publications
Howell, J.A., "Life Sciences- Stretching the Boundaries" Trans. I.Chem.E. Part C, Food and Bioproducts Processing , 78, 5-10, (2000) <text>
Smith,M., McFetridge,P., Bodamayali,T., Chaudhuri,J.B., Howell, J.A., Stevens, C.R. and Horrocks,M., "Porcine Derived Collagen as a Scaffold for Tissue Engineering", 78, 19-24, (2000)
Membrane bioreactors are useful for the treatment of various effluents, both municipal and industrial. We are interested in how these reactors can be used to intensify the removal of reclacitrant organics in the presence of inorganic compounds. We are designing membrane bioreactors to help intensify and accelerate the adaptation and evolution of micro-organisms to achieve new capabilities.Selected publicationsW. Liu, J.A. Howell, T.C. Arnot and J.A. Scott 'A Novel Extractive Membrane Bioreactor For Treating Bio-Refractory Organic Pollutants In The Presence Of High Concentrations Of Inorganics: Application To a Synthetic Acidic Effluent Containing High Concentrations Of Chlorophenol And Salt.' J.Membr.Sci. (in press) <text>